Perennial herb with a creeping rhizome 20 cm - 0.8 m tall Leaves: in whorls of four, ascending or loosely spreading, 1 - 3 cm long, 1 - 6 mm wide, linear to lance-shaped to reverse lance-shaped with a rounded tip, one-veined, sometimes slightly rough or roughly hairy along the margins and on the midrib beneath. Inflorescence: a long-stalked, ascending cluster of two to five short-stalked flowers. Flowers: white, 2 - 3.5 mm wide, more or less flat and circular in outline, with four short lobes. Lobes longer than wide, usually pointed. Stamens four, shorter than corolla. Styles two, short. Fruit: dry, indehiscent, 4 - 5 mm wide, spherical, paired, separating when ripe, one-seeded. Stems: matted, slender, four-angled, upright and branched, densely short-bearded at the nodes.
Similar species: No information at this time.
Flowering: mid-May to early August
Habitat and ecology: Occurring in low woods and, more often, in moist meadows. It is also found in moist calcareous habitats and in prairies.
Occurence in the Chicago region: native
Etymology: Galium comes from the Greek word gala, meaning milk, referring to the plants that are used to curdle milk. Obtusum means blunt.
Matted perennial, strict and branched from the base or diffusely branched throughout, 2-8 dm; stems smooth on the angles but densely short-bearded at the nodes; principal lvs in 4's, linear to lanceolate or oblanceolate, 10-30 נ1-6 mm, obtuse, the margins and the midvein beneath usually ±scabrous or hispid-ciliolate; infls short, almost all terminal, with 3-5 fls on short ascending pedicels, the pedicels in fr 5-10 mm, divaricate, stiff, smooth; fls white, 4-merous, 2-3.5 mm wide, the lobes longer than wide; frs 4-5 mm, ±tuberculate, often only one mericarp developed; 2n=48. Swampy thickets and moist meadows; N.S. and s. Que. to Minn. and S. D., s. to Fla. and Tex.
May-July. (G. tinctorium, misapplied) The widespread var. obtusum has the lvs mostly (2)3-5 mm wide, and has consistently bearded nodes. The var. filifolium (Wiegand) Fernald, from s. N.J. to Ga., often near the coast, has lvs mostly 1-2 mm wide, and the nodes are not always bearded.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.